Effect of shear-induced breakage and reflocculation on the floc structure, settling, and dewatering of coal tailings

• Autorzy: Fan Yuping , Ma Xiaomin , Song Shuai , Dong Xianshu , Chen Ruxia , Dong Yingdi

Identyfikatory

DOI

10.37190/ppmp/118148

• Języki publikacji: EN

Abstrakty

EN

Flocculation is crucial for the treatment of coal tailings in industries. In this paper, the effects of shear-induced breakage and reflocculation of the floc, settling, and dewatering of coal tailings were investigated. The results show that as shear strength increases, the settling velocity of flocculated tailings decreases. A shear rate of 200 rpm (170.6 s-1) leads to the loss of half the settling velocity. However, at high dosage cases, 200 rpm-300 rpm shear could improve the clarity of the supernatant. Small particles are flocculated preferentially, especially for particles below 10 µm. With the increase in dosage, the critical particle size for the occurrence of flocculation increases. The chaos index proposed can quantitatively reflect the degree of flocculation or reflocculation of coal tailings. At high dosage conditions, shear could enhance the dewatering performance of flocs by reconstructing the filter cake. Controlling the structure of flocs by dosage and shear strength can help obtain appropriate settling, clarifying, and dewatering performance of coal tailings.

Słowa kluczowe

EN

coal tailings; floc structure; shear; settling; dewatering

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Physicochemical Problems of Mineral Processing
• Rocznik: 2020
• Tom: Vol. 56, iss. 2
• Strony: 363--373
• Opis fizyczny: Bibliogr. 29 poz., rys., tab., wykr.

Twórcy

autor

Fan Yuping

• Department of mineral processing engineering, Taiyuan University of Technology, Taiyuan, Shanxi, China, 030024

autor

Ma Xiaomin

• Department of mineral processing engineering, Taiyuan University of Technology, Taiyuan, Shanxi, China, 030024

autor

Song Shuai

• Department of mineral processing engineering, Taiyuan University of Technology, Taiyuan, Shanxi, China, 030024

autor

Dong Xianshu

• Department of mineral processing engineering, Taiyuan University of Technology, Taiyuan, Shanxi, China, 030024

autor

Chen Ruxia

• Department of mineral processing engineering, Taiyuan University of Technology, Taiyuan, Shanxi, China, 030024

autor

Dong Yingdi

• Department of mineral processing engineering, Taiyuan University of Technology, Taiyuan, Shanxi, China, 030024

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